[coreboot-gerrit] Patch set updated for coreboot: 043c2fb northbridge/amd/amdht: Allow mainboards to set HT frequency limit

[Timothy Pearson (tpearson@raptorengineeringinc.com)]

Timothy Pearson (tpearson at raptorengineeringinc.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/8464

-gerrit

commit 043c2fbf580e9394adbec0924243a5d097f73578
Author: Timothy Pearson <tpearson at raptorengineeringinc.com>
Date:   Mon Feb 16 14:57:06 2015 -0600

    northbridge/amd/amdht: Allow mainboards to set HT frequency limit
    
    This is useful when the PCB layout of a mainboard does not allow
    stable operation at the increased HyperTransport speeds of newer
    processors.
    
    Change-Id: Idc93a1294608178ddf38ca72d40e6bad7deb9004
    Signed-off-by: Timothy Pearson <tpearson at raptorengineeringinc.com>
---
 src/northbridge/amd/amdfam10/amdfam10.h |  7 +++++++
 src/northbridge/amd/amdht/h3finit.c     | 29 ++++++++++++++++++++++++++---
 src/northbridge/amd/amdht/h3finit.h     |  3 +++
 src/northbridge/amd/amdht/ht_wrapper.c  |  3 ++-
 4 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/src/northbridge/amd/amdfam10/amdfam10.h b/src/northbridge/amd/amdfam10/amdfam10.h
index ab4b42e..af9e24e 100644
--- a/src/northbridge/amd/amdfam10/amdfam10.h
+++ b/src/northbridge/amd/amdfam10/amdfam10.h
@@ -1,6 +1,7 @@
 /*
  * This file is part of the coreboot project.
  *
+ * Copyright (C) 2015 Timothy Pearson <tpearson at raptorengineeringinc.com>, Raptor Engineering
  * Copyright (C) 2007 Advanced Micro Devices, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -1033,6 +1034,10 @@ struct nodes_info_t {
 	u32 up_planes; // down planes will be [up_planes, planes)
 } __attribute__((packed));
 
+struct ht_link_config {
+	uint8_t ht_speed_limit; // Speed in MHz; 0 for autodetect (default)
+};
+
 /* be careful with the alignment of sysinfo, bacause sysinfo may be shared by coreboot_car and ramstage stage. and ramstage may be running at 64bit later.*/
 #if !CONFIG_AMDMCT
 
@@ -1053,6 +1058,8 @@ struct sys_info {
 	u8 host_link_freq[NODE_NUMS*8]; // record freq for every link from cpu, 0x0f means don't need to touch it
 	u16 host_link_freq_cap[NODE_NUMS*8]; //cap
 
+	struct ht_link_config ht_link_cfg;
+
 	u32 segbit;
 	u32 sbdn;
 	u32 sblk;
diff --git a/src/northbridge/amd/amdht/h3finit.c b/src/northbridge/amd/amdht/h3finit.c
index 4059182..10973aa 100644
--- a/src/northbridge/amd/amdht/h3finit.c
+++ b/src/northbridge/amd/amdht/h3finit.c
@@ -75,6 +75,30 @@ static const uint16_t ht_speed_limit[16] =
 	 0x00FF, 0x007F, 0x003F, 0x001F,
 	 0x000F, 0x0007, 0x0003, 0x0001};
 
+static const uint16_t ht_speed_mhz_to_hw(uint16_t mhz)
+{
+	switch(mhz) {
+		case 200: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_200];
+		case 300: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_300];
+		case 400: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_400];
+		case 500: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_500];
+		case 600: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_600];
+		case 800: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_800];
+		case 1000: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_1000];
+		case 1200: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_1200];
+		case 1400: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_1400];
+		case 1600: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_1600];
+		case 1800: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_1800];
+		case 2000: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_2000];
+		case 2200: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_2200];
+		case 2400: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_2400];
+		case 2600: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_2600];
+		case 0: return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_AUTO];
+		default: printk(BIOS_WARNING, "WARNING: Invalid HT link limit frequency %d specified, ignoring...\n", mhz);
+		return ht_speed_limit[NVRAM_LIMIT_HT_SPEED_AUTO];
+	}
+}
+
 /*----------------------------------------------------------------------------
  *			TYPEDEFS AND STRUCTURES
  *
@@ -1359,10 +1383,9 @@ static void selectOptimalWidthAndFrequency(sMainData *pDat)
 
 	for (i = 0; i < pDat->TotalLinks*2; i += 2)
 	{
-		/* FIXME
-		 * Mainboards need to be able to set cbPCBFreqLimit
-		 */
 		cbPCBFreqLimit = 0xFFFF;		// Maximum allowed by autoconfiguration
+		if (pDat->HtBlock->ht_link_configuration)
+			cbPCBFreqLimit = ht_speed_mhz_to_hw(pDat->HtBlock->ht_link_configuration->ht_speed_limit);
 		cbPCBFreqLimit = min(cbPCBFreqLimit, cbPCBFreqLimit_NVRAM);
 
 #if CONFIG_EXPERT && CONFIG_LIMIT_HT_DOWN_WIDTH_8
diff --git a/src/northbridge/amd/amdht/h3finit.h b/src/northbridge/amd/amdht/h3finit.h
index 136a5cf..a56c246 100644
--- a/src/northbridge/amd/amdht/h3finit.h
+++ b/src/northbridge/amd/amdht/h3finit.h
@@ -1,6 +1,7 @@
 /*
  * This file is part of the coreboot project.
  *
+ * Copyright (C) 2015 Timothy Pearson <tpearson at raptorengineeringinc.com>, Raptor Engineering
  * Copyright (C) 2007 Advanced Micro Devices, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -462,6 +463,8 @@ typedef struct {
 		const u8 *pEventData0
 	);
 
+	const struct ht_link_config *ht_link_configuration;
+
 } AMD_HTBLOCK;
 
 /*
diff --git a/src/northbridge/amd/amdht/ht_wrapper.c b/src/northbridge/amd/amdht/ht_wrapper.c
index 3bf81c6..a38caa4 100644
--- a/src/northbridge/amd/amdht/ht_wrapper.c
+++ b/src/northbridge/amd/amdht/ht_wrapper.c
@@ -139,7 +139,8 @@ static void amd_ht_init(struct sys_info *sysinfo)
 		NULL,	// BOOL (*AMD_CB_CustomizeBuffers)();
 		NULL,	// void (*AMD_CB_OverrideDevicePort)();
 		NULL,	// void (*AMD_CB_OverrideCpuPort)();
-		AMD_CB_EventNotify	// void (*AMD_CB_EventNotify) ();
+		AMD_CB_EventNotify,	// void (*AMD_CB_EventNotify) ();
+		&sysinfo->ht_link_cfg // struct ht_link_config*
 	};
 
 	printk(BIOS_DEBUG, "Enter amd_ht_init()\n");